South Florida's Wednesday forecast calls for mostly cloudy skies with afternoon highs in the mid to upper 70s, overnight lows in the mid to upper 60s and a 40 percent chance of rain.

Because the winds are predicted to gust to almost 30 mph, beware of dangerous rip currents at the beaches. Boaters also should be on guard for rough seas.

Thursday also should be breezy.

The cooler conditions are the result of an arctic cold front that is predicted to drop temperatures into the low 50s tonight in Orlando and the mid 30s in Tallahassee, prompting a freeze warning to be issued for the northern part of the state.

Central Florida's Thursday forecast: Partly sunny and windy with highs in the upper 60s and lows in the lower 50s.

Water temp: From weather expert Jim Lushine:

The water temperature at Lake Worth Inlet has dropped to a bitter cold 79 degrees. Break out the ice fishing gear.

OK, maybe a bit of an exaggeration.

Just the same, long time residents will probably avoid the surf until next May when the water temperature will revert back to 80 degrees or more.

Compared to air temperature how much does the water temperature vary from night to day?

Without any major change in air mass, the water temperature, which is measured at a depth of 30 feet, changes about 1 degree from the low temperature at night to the high temperature during the afternoon.

Compare that to the air temperature, which varies about 10 degrees during the rainy season to about 15 degrees during the dry season.

As a comparison, the temperature change in Phoenix, Ariz., is about 30-plus degrees, thanks to the very low humidity there.